McqMate
These multiple-choice questions (MCQs) are designed to enhance your knowledge and understanding in the following areas: Electrical Engineering .
| 51. |
The travelling speed of cranes varies from |
| A. | 20 to 30 m/s |
| B. | 10 to 15 m/s |
| C. | 5 to 10 m/s |
| D. | 1 to 2.5 m/s |
| Answer» D. 1 to 2.5 m/s | |
| 52. |
Besides a constant speed a synchronous rotor possesses which of the following advantages ? |
| A. | Lower cost |
| B. | Better efficiency |
| C. | High power factor |
| D. | All of the above |
| Answer» C. High power factor | |
| 53. |
By the use of which of the followingm D.C. can be obtained from AC? |
| A. | Silicon diodes |
| B. | Mercury arc rectifier |
| C. | Motor generator set |
| D. | Any of the above |
| Answer» D. Any of the above | |
| 54. |
Which of the following motors is preferred when quick speed reversal is the main consideration? |
| A. | Squirrel cage induction motor |
| B. | Wound rotor induction motor |
| C. | Synchronous motor |
| D. | D.C. motor |
| Answer» D. D.C. motor | |
| 55. |
Which ofthefollowing motors is preferred when smooth and precise speed control over a wide range is desired ? |
| A. | D.C. motor |
| B. | Squirrel cage induction motor |
| C. | Wound rotor induction motor |
| D. | Synchronous motor |
| Answer» A. D.C. motor | |
| 56. |
For crane travel which of the following motors is normally used ? |
| A. | Synchronous motor |
| B. | D.C. differentially compound motor |
| C. | Ward-Leonard controlled |
| D. | C. shunt motor |
| Answer» D. C. shunt motor | |
| 57. |
The capacity of a crane is expressed in terms of |
| A. | type of drive |
| B. | span |
| C. | tonnes |
| D. | any of the above |
| Answer» C. tonnes | |
| 58. |
The characteristics of drive for crane hoisting and lowering are which of the following ? |
| A. | Precise control |
| B. | Smooth movement |
| C. | Fast speed control |
| D. | All of the above |
| Answer» D. All of the above | |
| 59. |
Which of the following motors is preferred for boom hoist of a travelling crane? |
| A. | Single phase motor |
| B. | Synchronous motor |
| C. | A.C. slip ring motor |
| D. | Ward-Leonard controlled D.C. shunt motor |
| Answer» C. A.C. slip ring motor | |
| 60. |
A wound rotor induction motor is preferred, as compared to squirrel cage induction motor, when major consideration is |
| A. | slop speed operation |
| B. | high starting torque |
| C. | low windage losses |
| D. | all of the above |
| Answer» B. high starting torque | |
| 61. |
Which of the following motors has series characteristics ? |
| A. | Shaded pole motor |
| B. | Repulsion motor |
| C. | Capacitor start motor |
| D. | None of the above |
| Answer» B. Repulsion motor | |
| 62. |
Which of the following happens when star-delta starter is used ? |
| A. | Starting voltage is reduced |
| B. | Starting current is reduced |
| C. | Both (A) and (B) |
| D. | None of the above |
| Answer» C. Both (A) and (B) | |
| 63. |
For a D.C. shunt motor which of the following is incorrect 7 |
| A. | Unsuitable for heavy duty starting |
| B. | Torque varies as armature current |
| C. | Torque-armature current is a straight line |
| D. | Torque is zero for zero armature current |
| Answer» A. Unsuitable for heavy duty starting | |
| 64. |
For which of the following applications motor has to start with high acceleration? |
| A. | Oil expeller |
| B. | Floor mill |
| C. | Lifts and hoists |
| D. | Centrifugal pump |
| Answer» C. Lifts and hoists | |
| 65. |
Which of the following types of motor enclosure is safest ? |
| A. | Totally enclosed |
| B. | Totally enclosed fan cooled |
| C. | Open type |
| D. | Semi closed |
| Answer» B. Totally enclosed fan cooled | |
| 66. |
While selecting motor for an air conditioner which of the following characteristics is of great importance ? |
| A. | Type of bearings |
| B. | Type of enclosure |
| C. | Noise |
| D. | Arrangement for power transmis¬sion |
| Answer» C. Noise | |
| 67. |
The diameter of the rotor shaft for an electric motor depends on which of the following ? |
| A. | r.p.m. only |
| B. | Horse power only |
| C. | Horse power and r.p.m. |
| D. | Horse power, r.p.m. and power factor |
| Answer» C. Horse power and r.p.m. | |
| 68. |
Which of the following alternatives will be cheaper ? |
| A. | A 100 H.P. AC. three phase motor |
| B. | Four motors of 25 H.P. each |
| C. | Five motors of 20 H.P. each |
| D. | Ten motors of 10 H.P. each |
| Answer» A. A 100 H.P. AC. three phase motor | |
| 69. |
The cost of an induction motor will increase as |
| A. | horsepower rating increases but r.p.m. decreases |
| B. | horsepower rating decreases but r.p.m. increases |
| C. | horsepower rating and operating speed increases |
| D. | horsepower rating and operating speed decreases |
| Answer» A. horsepower rating increases but r.p.m. decreases | |
| 70. |
In series motor which of the following methods can be used for changing the flux per pole ? |
| A. | Tapped field control |
| B. | Diverter field control |
| C. | Series-parallel control |
| D. | Any of the above |
| Answer» D. Any of the above | |
| 71. |
Word Leonard controlled DC Drives are generally used for..... excavators |
| A. | Light duty |
| B. | Medium duty |
| C. | Heavy duty |
| D. | All of the above |
| Answer» C. Heavy duty | |
| 72. |
......... is preferred for automatic drives |
| A. | Synchronous motors |
| B. | Word Leonard controlled DC motors |
| C. | None of the above |
| D. | Any of the above |
| Answer» D. Any of the above | |
| 73. |
The load cycle for a motor driving a power press will be ......... |
| A. | Variable load |
| B. | Continuous |
| C. | Continuous but periodical |
| D. | Intermittent and variable load |
| Answer» D. Intermittent and variable load | |
| 74. |
A reluctance motor........ |
| A. | Is provided with slip rings |
| B. | Requires starting gear |
| C. | Has high cost |
| D. | Is compact |
| Answer» D. Is compact | |
| 75. |
The size of an excavator is usually expressed in terms of |
| A. | Crowd motion |
| B. | Angle of swing |
| C. | Cubic metres |
| D. | Travel in metres |
| Answer» C. Cubic metres | |
| 76. |
In jaw crushers a motor has to often start against....... load |
| A. | Heavy |
| B. | Medium |
| C. | Normal |
| D. | Low |
| Answer» A. Heavy | |
| 77. |
........has least range of speed control |
| A. | Slip ring induction motor |
| B. | Synchronous motor |
| C. | DC shunt motor |
| D. | Schrage motor |
| Answer» B. Synchronous motor | |
| 78. |
In series motor which of the following methods can be used for changing the flux per pole? |
| A. | Tapped field control |
| B. | Diverter field control |
| C. | Series-parallel control |
| D. | Any of the above |
| Answer» D. Any of the above | |
| 79. |
Which of the following alternatives will be cheaper ? |
| A. | A 100 HP ac three phase motor |
| B. | Four motors of 25 HP each |
| C. | Five motors of 20 HP each |
| D. | 10 motors of 10 HP each |
| Answer» A. A 100 HP ac three phase motor | |
| 80. |
By the use of which of the following DC can be obtained from AC? |
| A. | Silicon diodes |
| B. | Mercury arc rectifier |
| C. | Motor generator set |
| D. | Any of the above |
| Answer» D. Any of the above | |
| 81. |
Besides a constant speed a synchronous rotor possesses which of the following advantages ? |
| A. | Lower cost |
| B. | Better efficiency |
| C. | High power factor |
| D. | All of the above |
| Answer» C. High power factor | |
| 82. |
Which of the following types of motor and enclosure is safest |
| A. | Totally enclosed |
| B. | Totally enclosed fan cooled |
| C. | Open time |
| D. | Semi closed |
| Answer» B. Totally enclosed fan cooled | |
| 83. |
Which feature while selecting a motor for centrifugal pump will be of least significance? |
| A. | Starting characteristics |
| B. | Operating speed |
| C. | Horse power |
| D. | Speed control |
| Answer» D. Speed control | |
| 84. |
Which part of a motor needs maximum attention for maintenance? |
| A. | Frame |
| B. | Bearing |
| C. | Stator winding |
| D. | Rotor winding |
| Answer» B. Bearing | |
| 85. |
While selecting an electric motor for a floor Mill, which electrical characteristics will be of least significance ? |
| A. | Running characteristics |
| B. | Starting characteristics |
| C. | Efficiency |
| D. | Breaking |
| Answer» D. Breaking | |
| 86. |
Which off the following motors is used for elevators? |
| A. | Induction motor |
| B. | Synchronous motor |
| C. | Capacitor start single phase motor |
| D. | Any of the above |
| Answer» A. Induction motor | |
| 87. |
...........is preferred for synthetic fibre mails |
| A. | Synchronous motor |
| B. | Reluctance motor |
| C. | Series motor |
| D. | Shunt motor |
| Answer» B. Reluctance motor | |
| 88. |
For derries and winches which of the following drives can be used ? |
| A. | Pole changing squirrel cage motors |
| B. | DC motors with word Leonard control |
| C. | AC slip rings motors with a variable resistance |
| D. | Any of the above |
| Answer» D. Any of the above | |
| 89. |
In........ method of starting three phase induction motors the starting voltage is not reduced |
| A. | Auto transformer |
| B. | Star Delta |
| C. | Slip ring |
| D. | Any of the above |
| Answer» C. Slip ring | |
| 90. |
For which off the following applications DC motors are still preferred? |
| A. | High operation |
| B. | Variable speed drive |
| C. | High starting torque |
| D. | Reversibility |
| Answer» B. Variable speed drive | |
| 91. |
Rotor of the motor is usually supported on........... bearings |
| A. | Ball or roller |
| B. | Needle |
| C. | Thrust |
| D. | Bush |
| Answer» A. Ball or roller | |
| 92. |
.............method of starting a three phase induction motor needs six terminals |
| A. | Resistance starting |
| B. | Auto transformer |
| C. | None of the above |
| D. | Star delta |
| Answer» A. Resistance starting | |
| 93. |
In a paper mill where constant speed is required |
| A. | Synchronous motors are preferred |
| B. | AC motors are preferred |
| C. | Individual drive is preferred |
| D. | Group drive is preferred |
| Answer» C. Individual drive is preferred | |
| 94. |
........is not a part of ball bearing |
| A. | Inner race |
| B. | Outer race |
| C. | Cage |
| D. | Bush |
| Answer» D. Bush | |
| 95. |
A pony motor is used for the starting which of the following motors ? |
| A. | Squirrel cage induction motor |
| B. | Schrage motor |
| C. | Synchronous motor |
| D. | None of the above |
| Answer» C. Synchronous motor | |
| 96. |
........ has relatively wider range of speed control |
| A. | Synchronous motor |
| B. | Slip ring induction motor |
| C. | Squirrel case induction motor |
| D. | DC shunt motor |
| Answer» D. DC shunt motor | |
| 97. |
Heat control switches are used in |
| A. | Transformers |
| B. | Cooling ranges |
| C. | Three phase induction motors |
| D. | Single face |
| Answer» B. Cooling ranges | |
| 98. |
An elevator Drive is required to operate in |
| A. | One quadrant only |
| B. | Two quadrants |
| C. | Three quadrants |
| D. | Four quadrants |
| Answer» D. Four quadrants | |
| 99. |
Belt conveyors offer ..........starting torque |
| A. | High |
| B. | Low |
| C. | Medium |
| D. | Zero |
| Answer» A. High | |
| 100. |
While selecting a motor for air-conditioner the feature of utmost importance is |
| A. | Type of enclosure |
| B. | Type of bearing |
| C. | Noise |
| D. | Power transmission arrangement |
| Answer» C. Noise | |
Done Studing? Take A Test.
Great job completing your study session! Now it's time to put your knowledge to the test. Challenge yourself, see how much you've learned, and identify areas for improvement. Don’t worry, this is all part of the journey to mastery. Ready for the next step? Take a quiz to solidify what you've just studied.